A fast way to measure the twist rate is to use your cleaning rod. Put a tight fitting patch on the jag and start into the bore. Put a piece of masking tape on the rod near the handle. Put a pen mark on the tape and measure the distance from the mark to the muzzle. Push the rod into the bore and stop after 1 revolution. Measure the distance to the muzzle again and subtract from the first measurement. The difference is the twist rate.

I have been handloading 300- and 350-grain bullets for my new H&R 1871 Buffalo Classic, chambered in 45-70; but I haven't been able to get any sort of respectable groups yet at the range. Maybe the rate of twist is too slow for those bullets. I had been assuming that it was 1:20" ; but I did not receive any manual with the rifle, so I am not sure what it is. Does anyone out there know? If it is a slower rate of twist than 1:20", I might have to stick to 400-grain bullets.

If it's any concillation, my "manual" for my classic is 2 pages long, and doesn't say a word about such nice to know info as "twist rates". It only says things like "don't shoot yourself", and only shoot "properly marked factory ammo", etc., etc... (IE, it's worthless). I will dig deeper later on this week, I think I have it written down somewhere from the old NEF site that Marlin used to run.

Also- you have the twist rate backwards. The faster twists are for the heavier bullets, not the other way around. Mine shoots 400-440 gr cast bullets fine, you just have to mind the tight throat, or have it reamed, or shoot a "bore riding" bullet, or "tapered" bullet. I'm getting the Lyman tapered mold for mine, supposed to shoot like a dream.

Thanks, guys. Your information was helpful.

SloPoke: Thanks for straightening me out about the twist rate. If my rifle won't group with shorter/lighter bullets, I guess it can't be because of too slow a twist rate. I suppose I will try the heavier bullets anyway, since the lighter ones don't seem to give accuracy.

I've had good luck with Meister Cast 405gr. FP bullets in my BC. Neat, 'cause I'm loading with a very mild load (13gr. Unique). I can shoot all day & not get sore, but it still has a nice bit of recoil. Mind you, this is for target & metal plate whacking. Cheap, too!
Loner